1. Field of the Invention
The present invention relates to telecommunications and, more particularly, to an interactive media system and method within an IP Multimedia Subsystem (IMS) architecture.
2. Description of Related Art
Many telecommunications networks and other enterprises provide interactive media services, e.g., audio services, that users can access by telephone. An interactive audio system typically receives a call from a user, receives audio input from the user, such as speech or DTMF tones, and responsively provide the user with services, such as information, voice mail access, e-mail access, Web browsing, voice activated dialing (VAD), or the ability to do banking or other transactions. An interactive voice response (IVR) system is an example of an interactive audio system. Traditionally, such interactive audio systems have been highly integrated, often with proprietary architectures, making the systems difficult to modify so as to increase capacity or to provide new services.
A distributed interactive media system has been described in U.S. application Ser. No. 10/414,545. The distributed media system described therein includes media resources, such as automatic speech recognition (ASR) engines and text-to-speech (TTS) engines that process media in a real-time packet format, under the control of a resource manager. An interactive application could be written in a predetermined format, e.g., such as a voice extensible markup language (VXML) document, and a voice browser in the distributed media system could interpret the VXML document and responsively invoke media resources, via the resource manager, to provide interactive media services to the caller. By using a distributed architecture and publicly available “open standard” protocols, the distributed interactive media system could be more easily updated than a traditional, highly integrated IVR.
However, the IP Multimedia Subsystem (IMS) architecture promulgated by the 3rd Generation Partnership Project (3GPP) is becoming increasingly influential. Relevant aspects of the IMS architecture are described in 3rd Generation Partnership Project, “Technical Specification Group Services and System Aspects,” 3GPP TS 23.228 v7.1.0 (2005-09), which is incorporated herein by reference. The IMS architecture specifies a multimedia resource function (MRF) that is split into a multimedia resource function controller (MRFC) and a multimedia resource function processor (MRFP). The IMS architecture further specifies that sessions are controlled by a call session control function (CSCF), in accordance with service logic in an application server (AS). These aspects of the IMS architecture are summarized in FIG. 1.
With reference to FIG. 1, the MRFP controls bearer media streams on the Mb reference point and provides resources to be controlled by the MRFC. The IMS architecture also specifies other tasks of the MRFP, including media stream sourcing (e.g., for multimedia announcements) and media stream processing (e.g., audio transcoding and media analysis). The tasks of the MRFC include (i) controlling the media resources in the MRFP and (ii) interpreting information from the AS and CSCF and controlling the MRFP accordingly. The IMS architecture also suggests using the Session Initiation Protocol (SIP) for the Mr reference point and H.248 for the Mp reference point.
Thus, the IMS architecture contemplates a “top-down” approach in which service logic in the AS controls the MRFP via the CSCF and the MRFC. This approach can create difficulties, however, when the MRFP is used to provide certain interactive media services that IVRs currently provide. In particular, some interactive media services may be facilitated by allowing the MRFP to initiating actions, instead of simply carrying out commands. Similarly, the protocols that the IMS architecture specifies for controlling the MRFP, i.e., SIP and H.248, are not well suited for controlling MRFP so as to provide interactive media services to callers.
Accordingly, there is a need to provide an interactive media system that can work within the IMS architecture.